12 replies to this topic

[Foogoo]

Habitat of collection:  Under rock, sandy soil

Length (from head to gaster):  6 mm, 4 mm
Color, hue, pattern and texture:  Black gaster, reddish-brown body
Distinguishing characteristics: Polymorphic
Anything else distinctive: 
Nest description: Exclusively beneath rocks and tunnels into soil below

 

These guys were very similar to the still-unknown colony I found under the rock at Chino/Carbon Canyon. Lots of alates and alate larvae/pupae. Sorry the pictures aren't great.

 

Habitat of collection:  Trail

Length (from head to gaster):  3-4 mm
Color, hue, pattern and texture:  Black gaster, reddish body
Distinguishing characteristics: 
Anything else distinctive: 
Nest description: Sandy nest mound

 

Pheidole?

 

Habitat of collection:  Trail

Length (from head to gaster):  2 mm
Color, hue, pattern and texture:  Black gaster, reddish body
Distinguishing characteristics: 
Anything else distinctive: 
Nest description: Sandy nest mound

 

Nearly identical to the previous but smaller. In fact, I thought they were the same until I dumped them into the same container (add that to my dumb mistakes thread). Looks to me like Dorymyrmex bicolor.

 

 

Habitat of collection:  Trail

Length (from head to gaster):  1 mm
Color, hue, pattern and texture:  Black gaster, reddish body
 

What the heck are these? They were moving across the trail by the thousands, if not hundreds of thousands (or more) if the same was occurring off trail.

 

 

[dspdrew]

It's hard to tell for sure without seeing these from the side, but here are my guesses.

 

#1 Solenopsis xyloni

#2 Dorymyrmex bicolor

#3 Pheidole or S. xyloni

[Foogoo]

#1 is significantly darker and larger than #3 though, I thought Solenopsis were a small species. How do Dorymyrmex compare in size with Solenopsis? Are there any dead giveaways to distinguish Pheidole vs. Solenopsis vs. D. bicolor? Because those three all look the same to me in the wild.

[dspdrew]

The first could possibly be S. invicta too, which would be darker in color. As for the size of Solenopsis, it depends what you consider small. S. xyloni and S. invicta range in size between 3 mm and about 6 mm within the same colony.

 

The dead give-away when it comes to the difference between Pheidole, Solenopsis, and Dorymyrmex would be this:

 

Pheidole and Solenopsis are both Myrmicinae and therefor have two petiole nodes, while Dorymyrmex is Dolichoderinae, which only has one.

Pheidole have spines, while Solenopsis do not.

[Foogoo]

Interesting, I guess that colony is not as special as I thought. I'm surprised I didn't find more, it was mostly Pheidole and Dorymyrmex that dominated the area.

 

Anyone have any clue about the bug? It was surreal how many there were.

[dspdrew]

Remember I'm just giving my best guess from what I can see in those pictures. Being that you found these in Southern California, if I could see them in person, I'm sure I could tell you the genera of all three after two seconds of looking at them, but pictures are a different story. Did you look at them with your microscope to confirm they have the characteristics I mentioned (one vs. two petiole nodes and spines vs. no spines)?

[Foogoo]

Remember I'm just giving my best guess from what I can see in those pictures. Being that you found these in Southern California, if I could see them in person, I'm sure I could tell you the genera of all three after two seconds of looking at them, but pictures are a different story. Did you look at them with your microscope to confirm they have the characteristics I mentioned (one vs. two petiole nodes and spines vs. no spines)?

 

Unfortunately no. I usually keep them in the freezer for better microscope pictures but I had too much on my plate last night and dumped them asap. 

[James C. Trager]

The bug looks like a nymph of one of the seed bugs, Lygaeidae, but hard to refine it more than that (at least for me it is). 

[dspdrew]

Oh one more thing I remembered when looking these over again. Both Pheidole and Solenopsis have well defined antennal clubs, while Dorymyrmex do not. You can see this in the pictures.

[gcsnelling]

The first is almost certainly S. invicta, that species is very common in the Chino area. The second is Dorymyrmex bicolor or whatever. Easy way to tell in the field is to crush one. Dorymyrmex will have some scent while Solenopsis will not. The third is probably S. xyloni, also very common in that area.

[dspdrew]

What I don't get is why I have never smelled anything when crushing Dorymyrmex.

[Foogoo]

What I don't get is why I have never smelled anything when crushing Dorymyrmex.

 

Ditto. Same with Tapinoma which the two friends I was with were commenting on the smell. 

[dspdrew]

Oh Tapinoma should smell terrible. I can assure you, if it doesn't smell, then either you're nose is plugged or it's not Tapinoma.